Safety switch for oil burners



P ,1 A. GlLETTQ-SR 2,806,102

SAFETY SWITCH FOR on. BURNERS Filed Feb. 25, 1955;

'2 Sheets- Sheet 1 I INVENTOR. 4407/5/10 671E775, f

ATTD RN EYS p 10, 1957 A. GILETTO, SR 2,806,102

SAFETY SWITCH FOR OIL BURNERS Filed Fb. 25, 1955 2 Sheets-Sheet 2 BY myam%.

ATTD R N EYS United States Patent Office SAFETY SWITCH FOR on. BURNERS Anthony Giletto, Sr., Philadelphia, Pa. Application February 25, 1955, Serial No. 490,546 1 Claim. c1. zoo-81.9

This invention relates to a safety switch, and more particularly to a safety switch for a burner such as an oil burner.

This invention is an improvement over the safety switch shown and described in my Patent No. 2,694,194, dated November 9, 1954.

The object of the invention is to provide a safety switch which will selectively break the circuit leading to an oil burner motor and simultaneously actuate a warning signal light upon the occurrence of an explosion or the like in the furnace.

Another object of the invention is to provide a safety switch which is of more rugged and simple construction than that shown in my prior patent, and wherein the switch of the present invention can be easily reset when the oil burner motor is to be started after the trouble has been diagnosed and repaired.

A further object of the invention is to provide a safety switch which is extremely simple and inexpensive to manufacture.

Other objects and advantages will be apparent during the course of the following description.

In the accompanying drawings, forming a part of this application, and in which like numerals are used to designate like parts throughout the same:

Figure l is a side elevational view of the safety switch, with parts broken away and in section and showing the position of the parts in normal use.

Figure 2 is a sectional view taken on the line 22 of Figure 1.

Figure 3 is a view similar to Figure 1, but showing the baffle plate moved as when an explosion occurs and with the rod shifted by the flange of the baflle plate.

Figure 4 is a sectional view taken on the line 4-4 of Figure 2.

Figure 5 is a sectional view taken on the line 5-5 of Figure 2.

Figure 6 is a sectional view taken on the line 6-6 of Figure 2.

Figure 7 is a wiring of the present invention.

Referring in detail to the drawings, the numeral 10 designates a flue or conduit which can be used for conveying away products of combustion from a furnace or the like, and the conduit 10 may be provided with an opening 11, Figure 1. A cylindrical casing 12 extends through the opening 11, and a bracket 14 may be secured to the outer surface of the casing 10 in any suitable manner. A set screw 13 extends through the bracket 14 and into engagement with the casing 12 so that by loosening the set screw 13, the casing 12 can be rotated or adjusted with respect to the conduit.

There is further provided an open rectangular frame 15 which is positioned within the conduit 10, and the frame 15 is secured to the inner end of the casing 12. The frame 15 includes a pair of spaced parallel arms 16 which have a web 17 connecting their ends together. A stop member 18 extends from the web 17, and the stop member diagram illustrating the hook-up 2,806,102 Patented Sept. 10, 1957 18 is in the nature of a lip which is abutted by the free end of a door or plate 19 so as to limit swinging move ment of the plate 19. A hinge pin 20 serves to pivotally or hingedly connect the plate 19 to the arms 16 of the frame 15.

A wall member 21 is secured to an end of the casing 12 by suitable securing elements 22, and the wall member 21 helps to prevent heat from the conduit 10 from injuring the parts in the housing 24. The wall member 21 may be secured to the casing 12 by suitable securing elements 22, and the housing 24 can be spaced from and secured to the wall member 21 by securing elements 23, Figure 2. Arranged within the casing 12 and secured to the wall member 21 is a cylindrical sleeve 25 which frictionally and slidably supports a push rod 26. A body member 27 which has a pulley shape is secured on the rod 26, and the body member 27 is positioned within the housing 24.

Secured within the housing 24 is a support member 28 which may have an L-shape, and a switch 29 is supported on the member 28. An actuating lever 30 extends from the switch 29, and the lever 30 includes an enlarged head 31 on an end thereof which is arranged in engagement with the body member 27. Thus, as the rod 26 is shifted back and forth, the lever 30 will be moved to thereby actuate the switch 29. A flange 32 extends transversely from an end of the plate 19, and the flange 32 abuts the inner end of the rod 26 as shown in the drawings.

Positioned in the housing 24 is a light bulb 33, and a window 34 which may be of transparent material is provided for observing the light bulb 33. The numeral 35 designates a motor which can be of conventional construction for operating the oil burner or the like, and the numerals 36 and 37 designate the power lines for supplying electrical energy to the assembly from a suitable source of supply.

The details of the switch 29 are shown in Figure 7, and the switch 29 may include spring fingers 38 and 40 which have contacts 39 and 41 that are mounted for movement into and out of engagement with respect to each other. The switch further includes spring fingers 42 and 43 which have contacts 44 and 45 that are mounted for movement into and out of engagement with each other. A U-shaped base 46 may be secured to the lever 30 for causing movement of the spring fingers.

A fitting 47 is provided for the passage therethrough of the wires which lead into the housing 24. The bulb 33 may be arranged in engagement with a socket 48' which is mounted in the housing.

Referring further to the wiring diagram of Figure 7, a wire 48 may lead from the light bulb 33 to the finger 43. A wire 49 may connect the finger 40 to the line 37. The oil burner motor 35 may be connected to the finger 38 through the medium of a wire 50 and a suitable wire or line can be provided for connecting the motor 35 to the line 36.

From the foregoing it is apparent that there has been provided a safety switch for an oil burner which is an improvement over the safety switch shown and described in my prior Patent No. 2,694,194. In use the frame 15 can be arranged transversely in the conduit 10 as shown in the drawings and the bracket 14 includes a curved portion which conforms to the exterior of the conduit 10 and is secured thereto. In use the plate or door 19 is normally in the position shown in Figure 1 so that the lip 18 limits swinging movement of the plate. Then, in the event that a fault or defect develops in the burner or furnace, as an explosion occurs, then the plate 19 will pivot about the pin 20 from the position shown in Figure 1 to the position shown in Figure 3 so that the flange 32 will bias the rod 26 from the position of Figure l to the position of Figure 3. This movement of the rod 26 causes movement of the body member 27 which in turn pivots the lever 30 since the head 31 is arranged in engagement with the body member 27. With the lever 30 in the position shown in Figure'2 or in Figure 7, the base 46 moves the contact 41 into engagement with the contact 39 so that the circuit to themotor 35is completed whereby the oil burner will function in the usual manner. However, with the rod 26 and body member 27 shifted to the position shown in Figure 3 by the pivotal movement of the plate 19 and flange 32, the lever 30 and base 46 will move from the position shown in Figure 7 to break the circuit between the contacts 39 and 41 to thereby deenergize or cut-off the motor 35. At the same time that the circuit to the motor 35 is broken, the base 46 will move .the contact 44 into engagement with the contact 45 to complete the circuit to the warninglight 33 which can be observed through the window '34. After the fault has been repaired or corrected, the rod26 canbe manually pushed in by means of the portion which projects out through the housing 24. By pushing in this rod 26 the parts can be returned to their normal position shown in Figures 1, 2 and 7 and'the oil burner will continue to operate in the usual manner until an explosion occurs again. The bafile door opens when there is an explosion, and such an explosion may be caused when the spark fails to ignite the oil which is pumped into the fire Ci12111lher or when the spark ignites the fumes in the chamber, and whether the explosion is small or large, the present invention will disconnect the oil burner before a fire can begin.

I claim:

In combination with a conduit provided with an opening therein, said conduit adapted to have products of combusting passing therethrough, a cylindrical casing projecting through said opening, a bracket surrounding a portion of said casing and secured to the outer surface of said conduit, a rectangular open frame positioned in said conduit and secured to the inner end of said casing, a plate hingedly. connected to said frame, a flange extending transversely from an end'of said plate and arranged at right angles to said plate, a wall member secured to an end of said casing, a housing spaced from and secured to said wall member, said wall member helping to prevent heat from the conduit from injuring the parts in the housing, a cylindrical sleeve extending through said casing and secured to said wall member, a rod slidably arranged in said sleeve and having its inner end abutting the flange on said plate, a body member having a pulley shape mounted on said rod and positioned in said housing, an L-shaped support member mounted in said housing, a switch secured to said support member and supported thereby, a lever extending from said switch and having an enlarged head thereon arranged in engagement with said body member so that as the rod is shifted back and forth, the lever will be moved to thereby actuate the switch, said switch comprising a first and second pair of spring fingers having contacts thereon and a U-shaped base secured to said lever for moving said fingers, the contacts of said first fingers being mounted for move ment into and out of engagement with each other, the contacts of said second fingers being mounted for movement into and out of engagement with each other, said rod extending through said housing and having an end extending beyond said housing, said frame including a pair of spaced parallel arms and a web extending between the ends of said arms, a lip extending from said web and defining a stop member which is abutted by the free end of the plate so as to limit swinging movement of the plate, and a securing element extending through said bracket and into engagement with said casing so that by loosening the securing element, the casing can be rotated 01' adjusted with respect to the conduit.

References (Cited in the file of this patent UNITED STATES PATENTS 534,631 Carpenter Feb. 26, 1895 1,171,192 Haas Feb. 8, 1916 1,351,779 Mather Sept. 7, 1920 1,475,697 Hartman Nov. 27, 1923 2,244,373 Powers June 3, 1941 2,435,143 Knauth Jan. 27, .948 2,529,688 Grupp Nov. 14, 1950 2,694,194 Giletto Nov. 9, 1954 

